You’ve probably seen the music industry data: Sales of physical music playback discs (CDs and SACDs) are dropping sharply. In their place have sprung up two alternatives: file-based music playback and streaming digital playback. The former, also known as computer audio playback, consists of music stored in digital file format on some sort of storage drive: a spinning hard drive, a solid-state drive (including USB flash drives), or a network drive. To enjoy file-based music playback, you must acquire music files, either by downloading them over the Internet or copying (ripping) them from your CDs. Music files can range from extremely high resolution to CD resolution to lossy compressed formats designed to minimize the space needed to store them. The distinguishing characteristic of file-based music playback is that you must possess the files you play back.
Streaming digital playback consists of music played over the Internet. You don’t have to possess any files at all, just subscribe to a service that has access to the files and will send them to you over the Internet when and where you want to play them. Usually, streaming services have huge libraries of music files, which allow you to hear a wide variety of music at various levels of quality. Until recently, most streamed files were the lossy compressed variety (e.g., MP3), and even if sound quality was your area of interest, the best quality streaming service readily available was CD quality; however, the file encoding technology known as Master Quality Authenticated (MQA) promises to make streamed high-resolution file playback available. It also drastically reduces the size of downloaded files, making the downloading process much faster.
The music industry data also tells us that the popularity of file-based music playback is waning, as streaming digital playback improves the sound quality it delivers. That makes sense; it’s far easier just to turn on your equipment, select the music you want to hear from a huge collection, and hit the Play button rather than have to download files and copy them to your storage medium first.
Which brings us (finally) to the subject of this review: Esoteric’s new N-05 Network Audio Player. The N-05 supports both file-based playback and streaming playback from two major services. It’s Esoteric’s first venture into the file-player/streamer market, so that the disc drive that normally fronts its DACs has been replaced by a file renderer, an ugly-sounding term for the circuit that converts a stored file into a bitstream that the DAC can decode into an analog signal. Esoteric makes some of the best SACD/CD players and DACs on the planet, some of which sell at stratospheric prices. But the N-05 falls into the mid-range pricing area: $6500. For that price, you get a music file renderer (player) and a DAC capable of playing PCM files up to 384kHz/24-bit and DSD files up to DSD128. The USB input accepts DSD256, but the internal renderer plays only up to DSD128. There aren’t many DSD256 files for sale yet, but their numbers are increasing. Not only capable of file-based playback, the N-05 also streams music from the Tidal online music service, for which a subscription is needed, and from the Qobuz music service, not available in the U.S. If $6500 seems expensive, keep in mind that Esoteric gear is made to the highest standard and $6500 is among the company’s lowest prices for audio gear. As with all Esoteric products, the N-05 comes with a three-year parts and labor warranty.
Many file-based music players provide some sort of internal storage—a hard drive or a solid-state drive—but the N-05 does not; you must provide an external drive, either a USB drive or a network attached storage (NAS) drive. Which should you get? Here is a summary of pros and cons:
USB drive advantages
- The cheapest form of high-capacity storage; single drives with 8 terabytes of storage capacity cost $250 or less.
- Readily available at your local office supply store or Best Buy.
USB drive disadvantage
- With the N-05, only the folder view of the remote-control ESS app (see below) is available.
NAS drive advantages
- Since NAS drives are installed on a network, files stored there can be played on any music playback device on the network—so you don’t need a separate copy on each music player device.
- NAS storage is easy to expand so its capacity can be huge.
- NAS drives are relatively easy to back up; mine has a one-button backup feature.
- NAS drives can be located outside your listening room so their slightly noisy operation won’t intrude on your listening environment and they won’t need space on your equipment rack.
NAS drive disadvantage
- Depending on the number of bays and drive size, they can be very expensive. They are designed to be left on continuously and use rugged hard drives.
Construction-wise, the N-05 is a typical Esoteric product: a chassis constructed of heavy brushed silver aluminum plates with a sculpted faceplate that curves gracefully around into the side panels. The term “audio jewelry” could have been coined to describe Esoteric products. If that construction sounds heavy, it is: 24 3/8 pounds. In addition to the external hard drive, you will need a local area network (LAN), a WiFi router, and an Apple iPad to run the app, which remotely operates the N-05.
Like Esoteric’s disc players, the N-05 can function as a stand-alone DAC, with SPDIF inputs on RCA and optical TosLink jacks, and a USB Type B input. There is also an Ethernet input to connect the N-05 to your LAN and a second USB Type A input into which you can plug an external USB drive (hard drive or flash drive). There is also an RCA digital output jack that enables you to use a DAC other than the one built into the N-05, but of course, it’s limited to the highest speed of SPDIF output (192kHz sampling rate/24-bit word length), too slow for the highest-resolution music files.
I can’t complain about having external digital inputs, but in my view, since the player part of the N-05 does exactly the same thing as a computer or external digital music player, those inputs seem less useful than those on Esoteric’s disc players or DACs. Actually, the fact that the N-05 is not a computer (or at least doesn’t look like one) is precisely why it will appeal to many users, who just want to turn it on and play music. The N-05 will play DSF, DFF, FLAC, Apple Lossless, WAV, AIFF, MP3, and AAC music files—virtually all commercially available files except MQA, a very new format with (so far) limited music file availability. Both balanced (XLR) and unbalanced (RCA) output jacks are provided to connect the N-05’s analog output to your amplifier or preamplifier. The volume control is in the app, allowing you to drive a power amplifier directly. Esoteric recommends leaving this volume control at the maximum setting, and adjusting the volume with a preamplifier or integrated amplifier.
Esoteric recognizes the sonic superiority of a really high-quality digital clock, so the N-05 uses a high-precision VCXO (voltage-controlled crystal oscillator) to supply “a highly accurate reference clock signal to the digital circuitry. The N-05’s large, custom-designed VCXO was jointly developed with Nihon Dempa Kogyo (NDK), a leading manufacturer of crystal oscillators, exclusively for high-quality audio playback. The cornerstone of quality sound, its large crystal element realizes both excellent center accuracy (±0.5ppm, as shipped from the factory) and extremely low levels of phase noise to ensure exceptional sound playback quality.”
But that’s just a start: Esoteric makes two even more accurate external clock units, the G-01 and G-02, both with styling identical to that of the N-05. The lower-priced $5000 G-02 would probably be matched to the N-05. The N-05 has input and output jacks for the external clock.
A music file player is only as good as its remote control app, and Esoteric’s app is called Esoteric Sound Stream, which runs only on iPads and is available free from (where else?) Apple’s App Store. I’ll discuss Esoteric Sound Stream in detail in the next section.
Esoteric marketing specialist Scott Sefton said that “the N-05 uses most of the same designs and circuitry as the K-05X SACD Player/DAC.” That means it uses dual Asahi Kasei Microdevices AK4490 DAC chips, which according to Esoteric’s website “are configured in four parallel and differential circuits (8 outputs) driving each channel.” Also, “technology developed for the Grandioso C1 (Esoteric’s $40,000 top-of-the-line linestage) is also employed in the DAC’s power supply, which features Electronic Double-Layer Capacitors super capacitors. This regulated power supply boasts a total capacity of 500,000µF per channel for exceptional low-frequency sound reproduction.” That’s more than many power amplifiers have!
Since the player and DAC share the same chassis, there’s no need for a connecting cable; and the two sections can share the same clock through an I2S connection, which is the least sonically degrading connection—it’s used internally on most CD players.
The actual sound of the player is affected by the settings used, which include upconversion to multiples of the input sampling rate, as well as conversion of incoming PCM files to DSD. You can also set the output of the renderer to a specific sampling rate up to DSD256. Like many DACs, the N-05 has several available filters, as well as an off position which doesn’t use a digital filter for PCM playback. There are two Finite Impulse Response (FIR) filters, with sharp and slow filter slopes, and two short-delay filters with sharp and slow filter slopes. There is also a filter that cuts off frequencies over 50kHz when playing DSD. If you’re worried about ultrasonic noise produced by DSD, that filter should reduce it. Other settings let you select which analog output you want to use, if any; and whether you want to use the digital output (I didn’t, so I turned it off). There are also a setting that automatically darkens the display after playback has stopped for 30 minutes, an automatic power saving setting, and a dimmer for the display. A very complete assortment of controls.
Setting Up and Using the N-05
You need to make three connections to get the N-05 up and running: a power cord, an Ethernet cable to your home network, and a connection of the output signal to your preamplifier or integrated amplifier. The network connection provides two functions: It connects the N-05 to the network storage where you store your music files, and it connects the N-05 to a WiFi router on your network which lets your iPad running the Esoteric Sound Stream app control the N-05’s operation. I connected the N-05 to my preamp using Audience Au24 SX balanced cables, and to my home network using an Ethernet cable. The drawing below shows how the N-05 connects to the home network.
If you buy your N-05 from a dealer, you probably won’t get to appreciate how well the unit is shipped: It’s packed in three nested boxes and trucked in on a pallet. Outside of personal delivery by the manufacturer, that’s the most carrier-proof shipping mode I’ve ever experienced.
The N-05’s designation as a network audio player tells you that the preferred file storage medium is a network drive. The primary purpose of a network NAS drive is to store and retrieve files, but since it has an internal computer processor, it can also run programs on its own, and for use with the N-05, the NAS should run the MinimServer program. MinimServer is free, although donations are encouraged. Many NASes come with MinimServer already installed, or at least with an installation program for it already installed. My QNAP TS251 came with a MinimServer installation program. Often, review components come with throw-away power cords, but the Esoteric cord looked pretty robust, so I used it for the review.
I downloaded the free Esoteric Sound Stream app to my iPad Air2. The set-up process was easy; all I had to do to get started was select the N-05 as the music player and the Minimserver program running on the NAS as the music library. It was also fast, scanning my NAS and preparing a display of all the music there in about five minutes. Many apps have taken over an hour to accomplish that task.
A typical audio component’s user interface consists of the knobs and switches on its front panel and a remote control, but a music player’s user interface is its remote app running on a tablet computer, in the N-05’s case, the aforementioned Esoteric Sound Stream app, which I’ll call ESS for short. It was straightforward to use ESS; all you do to play an album is tap its cover art, and ESS shows you the songs in that album, and when you tap one of the songs, ESS starts playing the songs beginning with the one tapped. That’s quite easy—if you’ve ever used a music playback app before. If not, it could be confusing. An icon that looks like a gear brought up the Setup menu, which is where I found the user guide for ESS. To reach it, tap Setup, then scroll down to the bottom of the Setup menu. Tap App, then About, then Help, then English Manual. An online user manual will be displayed. Just scroll down to see how to use ESS. You can also either read the manual online or if you’d like, perhaps print it out from Esoteric’s website.
ESS’ main screen is divided into three sections: the top section shows information about the selection that’s currently playing; the section on the bottom left shows the playlist of songs selected to play; and the bottom right section shows the library, the albums available to play. The Now Playing section provided lots of useful information, such as the sampling rate of the song being played and its file type. Another thing I appreciated was ESS’ “folder view” at the top of the Library section (not visible in the screenshot above), which lets you view the contents of your music storage folder as if it were a computer folder, which of course, it is. Sometimes that’s a more reliable way to find an album you want to play.
Setting up Tidal was child’s play. I tapped the Tidal button on the ESS screen, entered my Tidal user ID and password, and Tidal’s menu was displayed on the screen. Playing a song or album on Tidal was similar to playing a song or album in your library: just tap the cover art thumbnail for the song or album and it will be added to the playlist. If you want to hear an entire album, touch and hold your finger to its cover art and you’ll see several options for playing all the songs. The four buttons to the right of the cover art, from left to right, let you play a selection immediately, play the selection after the current selection finishes playing, add the selection to the end of the playlist, or clear the playlist and play the selection.
You can name and save a playlist if you want to play the same assortment of songs several times. Since I was playing the same list of selections using several different filters and upsampling, I created a review playlist of the selections I used so I wouldn’t have to select them individually each time I played them. There’s also an icon on the ESS screen that shows the newly installed albums in your library—very useful.
I started using no filter, then tried a couple of the available filters. I also tried an oversampling option. For most of the review I used the internal renderer, but to test the external inputs, I used an external server connected via USB cable.
In heavy rotation recently at Casa Forrester: Mari Kodama’s recording of all the Beethoven Piano Sonatas, a DSD64 Pentatone recording purchased from primephonic.com. I’ve enjoyed Kodama’s performances on CD and SACD (ripped to my hard drive, of course), but welcomed the opportunity to acquire all 32 sonatas in the superior-sounding DSD format. On Sonata No. 32 the piano sound was very powerful, yet detailed. I have always admired the way DSD piano recordings depicted hammer action on piano strings, and this recording is a good example. The N-05 projected the lower registers of Kodama’s Steinway D with considerable power, and the well-defined microdynamics revealed Kodama’s sensitive phrasing. Through the N-05, I could hear complete, accurate note production, beginning with the initial transient that occurred when a key was pressed and a hammer struck a string, followed by the sustain part of a note, where complete harmonics were portrayed, to the decay part, where the note dwindled off into silence. An amazing recording, reproduced in realistic detail.
Next up was old favorite “Miserere” from The Tallis Scholars’ album Allegri’s Miserere & Palestrina’s Missa Papae Marcelli, a 96/24 FLAC recording downloaded from gimell.com. This a cappella choral work, a setting of Psalm 51, was originally reserved for performance in the Sistine Chapel, and is performed here by a small choral group recorded in a church. The main group is located at the front of the soundstage, while a small solo group is located some distance behind the main group. The N-05 laid out the soundstage before me with considerable realism: The solo tenor appeared centered at the front of the soundstage, the rest of the main group was spread out between the speakers at the front of the soundstage. The solo group sounded appropriately distant, yet I was able to hear them in considerable detail as the soprano soared to a high “C.” Some digital components impose a smear of distortion when the distant solo group enters, but not the N-05. Also, the solo tenor’s voice was free from any edginess or distortion, which can be a problem with some components. Although he’s located front and center, there was a feeling of spaciousness around the tenor, as though he was singing in a large space, which, in fact, he was.
Another old fave, “Folia Rodrigo Martinez,” was ripped as an AIFF file from the CD La Folia 1490-1701 (Alia Vox AFA 9805). On it, Jordi Savall and his band re-create a historically informed performance of a musical work dating from the year 1490. If that sounds like stodgy, boring music, it’s actually one of the more rollicking fun pieces of any vintage I’ve heard. Through the N-05, the piece sounded quite detailed, beginning with the three opening whacks on the cascabels (sleigh bells), each of which sound slightly different, as they do on better components. The baroque guitar plays a tune that is echoed by a harp, and although they’re playing the same tune, the two instruments sound somewhat different. I’ve heard the difference sound more pronounced with some other, more expensive gear, however. The main tune is played by leader Savall on his viola da gamba, a lively melody that constantly varies in loudness and speed. Percussion instruments consisting of castanets, a wood block, and a drum accompany the melody—the castanets sound somewhat distant, and have a slight tendency to get blurred into the background. The drum extends surprisingly deep—I think it goes into the mid-20Hz range—and provides a foundation for the piece. The N-05 reproduced the drum with power and impact, though perhaps a smidgen less of both than I’ve heard from a few other components. Still, it was a good workout for the subwoofer. The wood block was audible throughout the piece, and the N-05 accurately portrayed the transients of strikes on the block. The viola da gamba’s harmonics sounded accurate, although I noted a slight brightness.
So I’ve used three different musical samples: a solo piano recorded in DSD format, a choral group recorded in high-resolution PCM format, and a small instrumental band, recorded from a CD: a variety of recordings. Now let’s see how those selections sound when we switch in a couple of the N-05’s filters. (The filters can be set through the use of the Menu button on the front panel.)
First, the FIR1 filter, described in the manual as “a steep roll-off…used to sharply cut signals outside the audio band.” This type of filter is sometimes known as a “brickwall” filter because its action outside the audio band is very drastic. It only works on PCM recordings, so I didn’t use the DSD recording here. On the “Miserere” track, I thought I heard two effects, both very subtle and hard to detect. First, I thought I detected a very slight hardness with the FIR1 filter switched in. Second, I thought the sound of distant solo group behind the main choral group was very slightly more diffuse, less defined. With the “Folia Rodrigo Martinez,” the effect was also slight; I thought the slight brightness or edginess increased a small bit, and I thought the castanets sounded a little smeared. (In case you’re wondering, yes, I did fully break in the FIR1 filter.)
OK, now let’s switch to the SDLY2 filter, which the manual describes as a “short delay filter with a slow roll-off…used to gently cut signals outside the audio band.” I picked this filter because I thought it would be the most different from the FIR1 filter. And it did sound different. On “Miserere,” the slight hardness seemed gone, while the sound of the solo group sounded “groupy-er,” or better defined. On “Folia Rodrigo Martinez,” the edginess was reduced, though was not totally gone, and the castanets seemed better defined. Of all the filter settings, I preferred the SDLY2 filter. There’s a DSD filter, too, which rolls off the response over 50kHz, to eliminate the extremely high frequency noise that DSD produces. I must confess I heard absolutely no change when I switched in the DSD filter; maybe those with more extended hearing and speakers with a super-tweeter could hear a difference.
The N-05 gives you the capability to upconvert PCM signals to higher sampling rates. One such option converts them to DSD256 signals, which I decided to try. I figured that if any upconversion were obvious, it would be the DSD upconversion, and I was right, it was obvious. On “Miserere,” I wasn’t smitten by the effect; the sound seemed somewhat homogenized, a bit rounded off. The sense of depth was good, but overall, the sound seemed a bit congested. If the N-05 were mine, I’d leave the upconversion turned off—a personal choice.
So there you have it. I didn’t want to spend a lot of time with filters and especially not with upconversion, since the effects are subtle and subject to personal preference. But since the options are there, I felt I should sample some of them and tell you what I found. Your reaction to them might be different than mine.
To evaluate the N-05’s external digital inputs, I suppose most people would plug in a computer, and that’s what I did; however, rather than use a PC, I used an SOtM sMS-1000SQ network music player that performs most of the functions the N-05 does. It plays DSD and PCM music files and is controlled by an app running on an iPad. It also streams Tidal, although not as straightforwardly as ESS. It’s even housed in an attractive chassis that looks nothing like a computer. It differs from the N-05 in that it doesn’t have an internal DAC, so it’s just what I needed to plug into an external digital input on the N-05 and use its internal DAC. I connected the SOtM network music player to the USB input on the back of the N-05, moved the network cable from the N-05 to the SOtM, turned it on, turned on the iPENG 9 app that controlled its functions, selected the USB input on the N-05’s front panel, and was ready to play music. I confess my expectations were that the SOtM playing into the N-05 DAC would sound indistinguishable from the N-05 player/DAC combination. Ha!
Beethoven’s Piano Sonata No. 32 had slightly weightier sound, with stronger upper bass. I heard a tad more detail and better definition of the overall formation of notes, with especially well-defined leading-edge transients. Great microdynamics made Kodama’s interpretation more exciting. “Folia Rodrigo Martinez” sounded rather different—most noticeable was the more extended and powerful bass drum, which had considerably more extension and impact. The slight brightness I had heard from the N-05 was no longer present. Castanets were noticeably better defined and didn’t merge into the background noise. Harp and guitar were more distinct and sounded clearly different—and more like a harp and guitar. “Miserere” also sounded different, though perhaps not as much. The main choral group was portrayed with more detail, so the individual voices were more distinctive. The solo tenor’s voice sounded more expressive; I could better hear how he phrased the words. The distant solo group sounded further behind the main group, yet I heard more detail in their individual parts. No hint of brightness was evident, although the high frequencies were quite well defined.
“How can that be?” the bits-is-bits crowd will ask. “All the player does is produce a bitstream that is sent to the DAC.” Doggone if I know why—all I do is report what I hear.
I used my SOtM network music player ($4000 with its sPS-1000 power supply) and a $5995 PS Audio DirectStream DAC. I used the same Audience Au24 SX balanced cables to connect the DAC to the preamplifier, and a $980 Audience Au24 SE USB cable to connect the server to the DAC. Right away, I appreciated that the ESS app provided more information about the file being played, including sampling rate and if it’s a DSD file, what speed DSD file it is—information missing from the iPENG 9 app. Otherwise, the iPENG 9 app performed essentially the same as the ESS app, including streaming music from Tidal, although setting up iPENG 9 to play Tidal was an exercise for computer geeks.
Beethoven’s Piano Sonata No. 32 sounded even more dynamic—downright thunderous in the climaxes. Kodama uses continuous tempo changes in phrasing the piece, and the SOtM/PS Audio system seemed to make those more obvious. The piano’s harmonic structure seemed just a bit more accurate. I’ve strained to differentiate differences between the N-05’s internal DAC and my PS Audio DirectStream DAC; both were excellent.
If I mostly preferred the sound of the SOtM/PS Audio combination to the sound of the N-05, remember their combined cost ($10,945 including a USB cable) was considerably more. And the N-05 only needed one shelf on my rack, another cost factor that should be considered. While I’ve always thought the SOtM player looked quite nice, next to the elegant N-05 it looked rather plain.
The Esoteric N-05 Network Audio Player is an auspicious entry into the world of file-based and streaming music playback. It sounds first-rate, looks gorgeous, is easy to set up and use—it’s the type of component that makes it hard for a reviewer to pick nits. A wide and useful assortment of filters lets you tweak the sound to suit your taste. The internal DAC is a beauty; if you have a digital device besides the N-05, you can use the N-05’s DAC to improve that device’s sound.
If you want a music player combined with an advanced DAC, check out this new Esoteric. If you want to get into file-based or streaming music playback but don’t want to deface your audio equipment rack with an ugly noisy computer, the Esoteric may be your ticket. Will the N-05 seriously encroach on the sales of Esoteric’s SACD players? I think not; as the data showed, audiophiles are increasingly turning to file-based and streaming music playback and the N-05 makes Esoteric-quality equipment available for that purpose. With the N-05, Esoteric’s first entry into the network audio player market is a winner. Bravo, Esoteric.
Specs & Pricing
Type: Combined music player and DAC
Formats supported: DSF, DFF, FLAC, Apple Lossless, WAV, AIFF, MP3, and AAC. PCM files up to 384/32, DSD files up to DSD128 via internal renderer and DSD256 via external USB input
Outputs: analog: RCA (unbalanced) and XLR (balanced); digital: SPDIF on RCA connector
Drive capacity: None (requires external USB drive or NAS)
Streaming services: Tidal and Qobuz
Dimensions: 17⅝” x 4¼” x 14⅛”
Weight: 24 3/8 lbs.
18 Park Way
Upper Saddle River, NJ 07458
Speakers: Affirm Audio Lumination speakers; JL Audio fathom f110 subwoofer
Amplifier: David Berning ZH-230
Preamplifier: Audio Research SP20
Digital source: SOtM sMS-1000SQ network music player with sPS-1000 power supply, QNAP T-251 NAS, PS Audio DirectStream DAC with Torreys operating system